The journey takes days, sometimes weeks, often on foot. The roads are too risky, so they hike through the bush, fleeing gunfire and bombs, and the widespread threats of rape, torture, kidnapping and death. Everything they bring, they carry or wear: a T-shirt and jeans, a dress, a cooking pot, a few photos or family heirlooms. By the time they reach the border, many have lost track of their spouses and children. Many have watched their loved ones die.

Every day, on average, more than 2,400 South Sudanese refugees cross the border into Uganda, escaping violence at home. Last week, a UN human rights commission warned that South Sudan is showing signs of "impending genocide" with the potential for a repeat of Rwanda, circa 1994. South Sudan, the world's youngest country, gained independence in 2011, but conflict flared in 2013 between President Salva Kiir and then-Vice President Riek Machar. A peace deal was struck in 2015, but violence reignited this past July. More than 1 million South Sudanese have sought refuge in other countries; Uganda shelters the most, with nearly 600,000.

Aid agencies struggle to keep pace. "The scale of the influx is unprecedented," says Lydia Wamala, communications officer for the U.N.'s World Food Program (WFP) in Uganda. "Eighty-six percent of the new arrivals are women and children, with few or no resources to start their lives anew."

The WFP is constantly recalculating its needs. In recent months, the organization has faced funding shortfalls in the tens of millions, and in August it cut food rations in half for all but the newest and neediest arrivals. Since then, acute malnutrition rates have risen, according to the UN refugee agency. And that leaves refugees more susceptible to other conditions such as malaria, tuberculosis and respiratory disease. The WFP needs $72 million for its operations between now and May. "If we do not receive new funding," Wamala says, "we will have a significant shortfall in March." And that could mean further cuts in food rations.

"The majority of the people are underfed in this settlement," says Veronica Mesiko Simon, a 40-year-old South Sudanese tailor and mother of six who fled her home in July and now lives in Pagirinya Settlement in northern Uganda. Yet, like thousands of others, she sees Uganda as her family's only hope. "I would love to go back to my country when there is peace. But now, if there is constant fighting, it is becoming unbearable."